Musicians are generally not at all satisfied with currently available electronic guitar and violin controllers. This dissatisfaction extends to both professional level and amateur level devices.
Real stringed instruments can be plucked, struck, tapped, rubbed, bowed, muted and so on with one or both hands. Some of these gestures, such as striking and muting, can be combined to create new gestures such as hammer-ons and hammer-offs (alternate striking and muting with one or both hands), slapping, thumping, etc. Although stringed instrument controller and synthesizer systems do afford a wide range of interesting sounds, they do not afford the same range of gestures as an actual acoustic or electric instrument.
FIG. 1 shows a typical guitar controller and synthesizer system 50. This FIGURE shows how a traditional guitar 52 (usually electric, but possibly acoustic) is connected to a conventional synthesizer 54 through a pitch and amplitude detector 56. Through the use of a special electric guitar pickup 56, the pitch and amplitude detection can be replicated for each string, yielding polyphonic (muiti-voice) synthesizer control. The latency required for detecting pitch and amplitude, however, combined with the limitations of using only these two attributes of the instrument sound, are a significant part of the performance problem with traditional controller synthesizer devices. Mapping the detected pitch and amplitude into traditional MIDI (Musical Instrument Digital Interface) messages such as NoteOn, NoteOff, Velocity and PitchBend grossly limit the musician's expressive power when compared with the expressive power they have on a traditional acoustic or electric guitar. In addition, when using the traditional devices, selecting the correct synthesis algorithms and parameter mappings that best utilize the simple MIDI parameters is a difficult task that is beyond the capabilities of many music synthesizer users.
FIG. 1 is also applicable to violin synthesizer control systems (such as the Zeta violin family). Since the violin has bowing parameters as well as continuous pitch control, systems such as this suffer even more profoundly from the limitations of pitch and amplitude detection, MIDI, and the difficulties of synthesizer algorithm selection and parameterization.
FIG. 2 shows another configuration of a guitar controller 60 and synthesizer 54. This type of controller 60 is not made from a traditional acoustic or electric guitar. Rather, in this type of system, a specialized controller 60 is used that uses sensors to determine such things as finger placement, picking, string bend, and so on. Signals representing these parameters are converted to control messages, usually using MIDI, and sent to a synthesizer 54. Systems such as this can have advantages over the system of FIG. 1, in that they do not introduce the delays associated with pitch and amplitude detection. But such systems still suffer from the limitations of MIDI, and the mismatch between the control paradigm (guitar playing) and the synthesis algorithm.
Neither the system shown in FIG. 1 nor the one shown in FIG. 2 provide the intimacy of control (timing and subtlety of interaction parameters), or the range of means of interaction with the synthesis algorithm, that an actual acoustic or electric guitar provides. Part of the problem stems from the fact that in these systems there is a distinction between "audio signals" and "control signals." While there is a difference of bandwidth, related to the rate of change of a signal, between different control interface locations and modalities in real (e.g., acoustic) instruments, making this distinction artificially and too early in the design process has led to the inadequacy of many synthetic instrument controllers.
It is a goal of the present invention to provide a music synthesizer having minimum latency and in which control and synthesis are merged into one device. Another goal of the present invention is to provide a music synthesizer capable of responding to gestures such as plucking, striking, muting, rubbing, bowing, slapping, thumping and the like. Restated, the synthesizer should be responsive to and the audio frequency output signal it generates should be distinctively responsive to a variety of respective user gestures.